Flash Flood in Ontario County, New York

Flash Flood in Ontario County, New York: 65 recorded events between 1996 and 2025. The strongest on record measured 0. That places the county #389 nationally and #22 statewide for this hazard.

Reporting practice changed over time — early decades are undercounted, not calmer.

The busiest decade for flash flood in Ontario County is the 2010s, when 23 of the county's 65 recorded events were logged. Comparing decades is useful for spotting active periods, but the earliest years are thin because systematic reporting for this hazard began later.

Within the Ontario County archive, flash flood makes up 13.0% of all recorded severe weather across 8 hazard types. Nationally the county sits at #389 for this hazard and #22 within New York, putting it in the 87.2 percentile of all U.S. counties.

Jul is the peak month for flash flood in Ontario County with 27 recorded events, while Feb is the quietest. Seasonality here is a property of the archive as much as the climate: reports cluster where population and spotter networks are densest.

• Thunderstorm Wind 346
• Hail 50

How many flash flood events are on record in Ontario County, New York?

65 flash flood events are recorded in Ontario County between 1996 and 2025, causing 0 direct deaths.

What is the strongest flash flood recorded in Ontario County?

The strongest flash flood on record in Ontario County measured 0.

Where does the flash flood data for Ontario County come from?

All events come from the NOAA/NCEI Storm Events Database, the federal public-domain archive of severe weather reports. Dates are UTC, damage is as reported and not inflation-adjusted, and the most recent entries may still be revised.